The invention relates to adapters for connecting attachments to moving or lifting machinery. More particularly, the invention relates to an attachment plate and locking mechanism for securing attachments to construction equipment such as a skid steer loader.
A wide variety of versatile motorized mobile base power units are used in the construction, maintenance, and grounds-upkeep industries. These include skid steer loaders, light tractors and other compact power units. Skid steer loaders, in particular, are widely employed for a variety of material handling, earth moving, and transportation tasks.
In general, these devices are favored for their compact size, maneuverability and versatility. The versatility of these units is largely dependent upon their ability to use a wide variety of available attachments. The variety of available attachments is enormous. Attachments include buckets, grapples, tree spades, backhoes and many others.
These attachments are interchangeable by virtue of a universal mounting plate on the attachment which is securable to an attachment plate on the lift arms of any given loader. Currently available attachment plates engage the attachment mounting plate by placing a beveled upper edge beneath a downward-angled flange on the mounting plate. Once the beveled edge is engaged under the downward-angled flange, a latching mechanism is secured to releasably attach the mounting plate to the attachment plate.
The latching mechanisms of currently available attachment plates are manually operated, and in general, engage a series of sliding bolts or pins on the attachment plate into a mating series of holes on the mounting plate. Thus, it is necessary for the operator of the equipment to shut down the equipment, exit the operator""s position, and engage the latching mechanism manually, or to employ a helper to engage the latching mechanism manually. This situation creates a safety risk for the operator or helper, in that they must enter the operational area of the equipment while engaging the latching mechanism. The pins or bolts employed in these latching mechanisms are large and heavy in order to bear the substantial load stresses involved in operating the attachment. Additionally, precise alignment of the attachment plate and the mounting plate is required in order to engage the pins or bolts into their mating holes. If precise alignment is not achieved by manipulating the lift arms of the loader when engaging the attachment plate to the mounting plate, it is sometimes necessary for the operator or helper to manually shift the attachment, creating inconvenience and further safety risk.
Further, construction equipment is operated in an environment filled with dirt and debris. Items of dirt and debris may become lodged in the attachment latching mechanism, interfering with its operation. If this occurs the mechanism must often be cleaned manually, creating delay and inconvenience.
When it is desired to remove an attachment from the loader, it is necessary once again for the operator or helper to enter the operational area to manually disengage the latching mechanism, again creating inconvenience and a potential safety risk. It would be desirable to have an attachment plate and latching mechanism that is self-centering, requiring only approximate alignment with the mounting plate, and self-engaging, eliminating the need for manual intervention to latch the attachment plate to the mounting plate. In addition, it would be desirable to increase convenience and economy by making the attachment plate releasable without the need to employ a helper or for the operator to shut down and exit the machinery in order to release the attachment from the attachment plate of the loader. Further a self cleaning latching mechanism would be very helpful.
The present invention is an automatic attachment adapter which provides for safe, solo operation in the connection and removal of attachments from a skid steer loader or the like. The automatic attachment adapter employs a compact, lightweight, high strength latching device to make connection between the attachment plate of the loader and mounting plate of the attachment. Further, the latching device is self-centering, requiring only approximate alignment to operate. In addition, there is no need to enter the operational area of the equipment for manual engagement or disengagement of the latching mechanism, which creates a safer, more efficient, and more economical work environment.
This system employs a mounting plate on the attachment which has at its upper edge a downward-angled flange. Near the lower edge, it employs at least one pin to which the latching mechanism of the mating attachment plate engages. The attachment plate on the lift arms of the loader includes an angled upper edge for engaging the angled flange of the mounting plate and at least one latching mechanism which engages the pin on the mounting plate of the attachment.
The latching mechanism comprises a body housing and two rotating clevises which rotate on posts within the body housing. Each rotating clevis has a mouth, defined by an inner jaw and an outer jaw. The rotating clevises are able to be fully opened or to engage in one of two locking positions when closing. When open, the mouths of the paired rotating clevises overlap providing a relatively wide receiving area for receiving a mating pin for engagement. Once the engaging pin is in the receiving area, the rotating motion of the paired rotating clevises tends to force the pin to a centered location, creating a self-centering latch mechanism.
As the pin self-centers between the rotating clevises, the rotating clevises tend to close with relation to each other, achieving a first locked position, at which point the pin cannot be disengaged without unlocking the rotating clevises. Further travel inward reaches a second locked position, at which the mouths of the rotating clevises are fully meshed and the pin is engaged with great strength. This intermeshing of the rotating connectors creates a high-strength attachment between the attachment plate of the loader lift arms and the mounting plate on the attachment.
It is notable that once the beveled upper edge of the attachment plate is engaged beneath the angled flange of the mounting plate, the natural lifting motion of engaging the attachment causes the pins on the mounting plate to engage the latching mechanism rotating clevises, which encourages automatic engagement of the pins by the latching mechanism.
When it is desired to release the attachment from the loader, the latching mechanism can be remotely disengaged. The latching mechanism is well adapted to be disengaged by any of a variety of remote operating mechanisms. These mechanisms include a simple cable release, pneumatic mechanisms, hydraulic mechanisms, and electric servo-motor or solenoid mechanisms.
The latch mechanism is self cleaning. The rotating clevises are biased to an open position by springs or other biasing means. The opening motion of the latching mechanism tends to push debris out of the housing thus clearing it out of the mouths of the rotating clevises.